User:MAYIUA/Beta2-adrenergic agonist

Beta2-adrenergic agonist

Mechanism of action

 * Similar wording to other resources cited

Adverse effects
The overuse of short-acting β2 agonists has been found to contribute to poor asthma control, as high doses of β2 agonists are associated with an increased risk of asthma exacerbations and asthma-related hospitalizations.

Overuse of β2 agonists and asthma treatment without proper inhaled corticosteroid use has been associated with an increased risk of asthma exacerbations and asthma-related hospitalizations. Asthma treatment guidelines advise against β2 agonist-only treatment for asthma and recommend the addition of an inhaled corticosteroid to reduce the risk of exacerbations and improve asthma control.


 * Information on "large doses" of β2 agonists – inappropriate use of rescue inhaler without an inhaled corticosteroid.
 * GINA guidelines list SABA-only asthma treatment, SABA overuse, and ICS misuse as risk factors for exacerbations
 * Mechanism of action for overuse: associated with β2 receptor down-regulation and ICS use reversing down-regulation (?)
 * Inhaler excipients (particularly sulphite) and how they contribute to side effects – only finding information on sensitivities/allergies to different excipients. consider removing

Delivery
All β2 agonists are available in inhaler form, as either metered-dose inhalers which dispense an aerosolized drug and contains propellants, dry powder inhalers which dispense a powder to be inhaled, or soft mist inhalers which dispense a mist without use of propellants. Salbutamol (INN) or albuterol (USAN) and some other β2 agonists are available for use in a nebulizer. Nebulizers continuously deliver aerosolized drug and salbutamol delivered through nebulizer was found to be more effective than IV administration.

Terbutaline can be used for premature labour, in which it is typically administered by subcutaneous injection or intravenously.


 * Inhalers besides MDIs and DPIs (soft mist inhalers and nebulizers)
 * Oral and IV delivery of β2 agonists – Select β2 agonists have also been used in oral and IV dosage forms.
 * Nebulized albuterol/salbutamol found to be more effective than systemic administration. Albuterol/salbutamol available in MDIs, unit doses for nebulizers, and as oral syrup and tablets. – find information on efficacy of oral administration
 * Uses for different delivery methods
 * Terbutaline given through subcutaneous injection and IV infusion for premature labour, with good success and minimal risk to mother and fetus . Are IV β2 agonists commonly used for premature birth? + article cites an RCT, preterm birth article has citations for β2 agonist use.
 * IV is also used for severe asthma. (guidelines?)
 * Oral has been studied for use in fetal arrhythmias. (but i don't think it's used?)

Types

 * Look into specific durations, more combination products


 * LABA article also missing citations for the duration of action